高速离心泵推力滑动轴承承载能力分析

发布时间：2019-01-16 04:13

【摘要】：高速离心泵是现代工业机械中的一类基础设备，其在工业生产中起着越来越重要的作用，广泛应用于航空航天、石油化工、能源、制药、采矿、纸浆造纸等诸多行业。高速离心泵结构复杂，其主轴系统使用二级齿轮增速系统，高速轴转速高达每分钟上万转。针对此种工况，高速离心泵主轴系统选用滑动轴承进行支承。滑动轴承工作平稳、可靠、无噪音，在充分液体润滑的条件下，，滑动表面摩擦损失较小，并具有一定的吸振能力。滑动轴承作为高速离心泵的重要部件之一，其性能直接关系到高速离心泵的可靠性以及运行寿命。随着高速离心泵技术的发展，主轴越来越高的转速对滑动轴承的稳定性和承载能力提出了新的挑战。所以，为了提高高速离心泵运行时的安全性和可靠性，延长轴承的使用寿命,合理确定形位公差、装配间隙，降低成本，所以需要对滑动轴承的承载能力进行研究。本文采用有限体积方法，通过数值分析计算和仿真相结合的方法，对推力滑动轴承的承载能力进行研究。首先运用Ansys-CFX软件对高速离心泵内部流场进行三维数值模拟，计算主轴所受轴、径向载荷分布情况。再将有限体积法应用到滑动轴承动、静态特性分析之中，建立了一条滑动轴承润滑性能分析的框架模式。建立动静态雷诺控制方程、划分网格、并对控制方程作无量纲处理，应用有限体积法对方程进行离散，最终采用逐点松弛法利用Matlab软件自行编程进行迭代求解，从而计算轴承承载能力、刚度和阻尼系数等数据，并分析了系统的稳定性和转速、初始油膜厚度参数等输入参数的改变对润滑性能地影响。最终运用Ansys-Fluent软件对滑动轴承润滑状况进行流场运动仿真，计算轴向力分布，将仿真和数值计算的结果进行比较，结果基本一致，验证了有限体积法在滑动轴承流体润滑分析计算的可行性和正确性。本文通过对推力滑动轴承承载能力的深入研究,表明推力滑动轴承具有承载力高、稳定性好的优点，可以适应高速离心泵高速转轴的要求,为动压润滑推力滑动轴承的工程设计及应用提供了理论技术参考，为今后进一步的研究打下理论基础。
[Abstract]:High speed centrifugal pump is a kind of basic equipment in modern industrial machinery, which plays a more and more important role in industrial production. It is widely used in aerospace, petrochemical, energy, pharmaceutical, mining, pulp and paper making and many other industries. The structure of high speed centrifugal pump is complex, its spindle system uses two-stage gear increasing system, the speed of high speed shaft is as high as ten thousand revolutions per minute. In view of this condition, the spindle system of high speed centrifugal pump is supported by sliding bearing. The sliding bearing works stably, reliably and noiselessly. Under the condition of sufficient liquid lubrication, the friction loss of sliding surface is relatively small, and the sliding bearing has certain vibration absorption ability. As one of the important components of high speed centrifugal pump, the performance of sliding bearing is directly related to the reliability and service life of high speed centrifugal pump. With the development of high-speed centrifugal pump technology, the increasing speed of spindle poses a new challenge to the stability and bearing capacity of sliding bearings. Therefore, in order to improve the safety and reliability of high-speed centrifugal pump, prolong the service life of bearing, determine the tolerance of shape and position reasonably, assemble clearance and reduce the cost, it is necessary to study the bearing capacity of sliding bearing. In this paper, the bearing capacity of thrust sliding bearing is studied by using the finite volume method and the method of numerical analysis and simulation. Firstly, Ansys-CFX software is used to simulate the internal flow field of high speed centrifugal pump, and the axial and radial load distribution of the spindle is calculated. Then the finite volume method is applied to the analysis of the dynamic and static characteristics of sliding bearings, and a frame model for lubricating performance analysis of sliding bearings is established. The dynamic and static Reynolds control equations are established, the control equations are meshed, the governing equations are dimensionless, the finite volume method is used to discretize the equations, and the point-by-point relaxation method is used to solve the equations iteratively by using Matlab software. The bearing capacity, stiffness and damping coefficient of the bearing are calculated, and the influence of the input parameters, such as the stability and rotational speed of the system, the initial oil film thickness, on the lubrication performance is analyzed. Finally, the flow field motion of sliding bearing lubrication is simulated by Ansys-Fluent software, the axial force distribution is calculated, and the results of simulation and numerical calculation are compared, the results are basically the same. The feasibility and correctness of finite volume method in fluid lubrication analysis of sliding bearing are verified. By studying the bearing capacity of thrust sliding bearing, it is shown that thrust sliding bearing has the advantages of high bearing capacity and good stability, and can meet the requirements of high-speed rotary shaft of high-speed centrifugal pump. It provides a theoretical and technical reference for the engineering design and application of hydrodynamic lubricated thrust sliding bearings and lays a theoretical foundation for further research.
【学位授予单位】：南京林业大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH311

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